Occurrence of Phthalate Metabolites in Human Urine from Several Asian Countries

Abstract

The occurrence of 14 phthalate metabolites was found in human urine samples collected from seven Asian countries: China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam. Phthalate metabolites were found in all samples, indicating widespread exposure of humans to phthalates in these Asian countries. The highest total (the sum of 14 phthalates) phthalate metabolite concentrations were found in samples collected from Kuwait (median: 1050 ng/mL), followed in decreasing order by samples from India (389 ng/mL), China (234 ng/mL), Vietnam (133 ng/mL), Japan (120 ng/mL), Korea (117 ng/mL), and Malaysia (94.9 ng/mL). The creatinine-adjusted median concentrations of total phthalates for urine samples from Kuwait, India, China, Vietnam, Japan, Korea, and Malaysia were 692, 506, 289, 119, 103, 104, and 169 μg/g creatinine, respectively. Monomethyl phthalate (mMP), monoethyl phthalate (mEP), mono (2-isobutyl phthalate) (miBP), mono-n-butyl phthalate (mBP), and metabolites of di-(2-ethylhexyl) phthalate (DEHP) were the dominant compounds, collectively accounting for >95% of the total concentrations in the samples from the seven countries. The profiles of urinary phthalate metabolite concentrations varied among the samples collected from the seven countries. Urine samples from Kuwait contained the highest concentrations of mEP (median: 391 ng/mL), mBP (94.1 ng/mL), and the metabolites of DEHP (202 ng/mL), whereas samples from China and Japan contained the highest concentrations of miBP (50.8 ng/mL) and mMP (17.5 ng/mL), respectively. mEP was the predominant metabolite in urine samples from India and Kuwait (accounting for 49% of the total), mBP and miBP were the predominant compounds in samples from China (52%), and DEHP metabolites were the predominant compounds in samples from Korea (46%) and Vietnam (52%). Based on the urinary concentrations of mEP, mBP, miBP, and DEHP metabolites of the samples from the seven Asian countries, we estimated daily intake rates of diethyl phthalate (DEP), dibutyl phthalate (DBP), and DEHP. The results indicated that people in the seven Asian countries are exposed to DEP, DBP, and DEHP at levels well below the reference doses (RfD) suggested as unsafe by the U.S. Environmental Protection Agency (EPA). The estimated exposure doses to DEHP in Kuwait, however, were above the RfD recommended by the EPA.

Levels of Phthalate Metabolites in Urine of Pregnant Women and Risk of Clinical Pregnancy Loss

“…5−7 It has been proven that humans are continuously exposed to these chemicals through ingestion, inhalation, dermal absorption, and contact with medical devices, and consequently, phthalate metabolites have been detected in urine in nearly 100% of individuals from various countries. 8 −10 It has been demonstrated that long-term exposure to low concentrations of phthalates could cause adverse effects, such as hepatocarcinogenicity and endocrine disruption, in laboratory animals. Several epidemiological studies suggested that exposure to phthalates was associated with key features of metabolic syndrome [increased body mass index (BMI), abdominal adiposity, and insulin resistance], 11−13 although the results may be controversial.…”

Gender-specific relationship between prenatal exposure to phthalates and intrauterine growth restriction

“…Urinary phthalate metabolites were analyzed using a method modified by Guo et al (38). Briefly, 0.5 ml of urine sample was enzymatically hydrolyzed and purified by solid-phase extraction.…”

Associations of urinary 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine with phthalate exposure and semen quality in 562 Chinese adult men

“…Humans may be exposed to these chemicals via ingestion, inhalation, and dermal absorption (Wittassek et al, 2011). Urinary metabolites of phthalates have been widely detected in different human populations Guo et al, 2011;Joensen et al, 2012). Human epidemiologic studies have reported associations between exposure to some phthalates and adverse male reproductive outcomes, including reduced sperm quality, increased sperm DNA damage, and altered serum hormone levels, although these associations are not entirely consistent (Bloom et al, 2015;Duty et al, 2003;Hauser et al, 2006;Hauser et al, 2007;Lenters et al, 2015;Joensen et al, 2012;Mendiola et al, 2012;Specht et al, 2014;Thurston et al, 2015;Wang et al, 2015aWang et al, , 2015b.…”